Apparatus and method capable of erasing content displayed on touch screen

ABSTRACT

An apparatus capable of erasing content includes a touch display unit, a time calculating time, a storage unit, an area detecting unit, a control unit, and an erasing unit. The touch display unit determines a first touched place of a touch operation applied by an input apparatus on the touch display unit, a touch area of the first touched place, and a touch trace of the touch operation according to changing of touch coordinates. The control unit activates the time calculating unit to calculate a time duration of the touch operation when the size of the touch area is larger than the predetermined area size, and generates an erasing signal when the touch trace matches a predetermined trace pattern. The erasing unit erases content covered by the touch trace on the touch display unit in response to the erasing signal. A related method is also provided.

BACKGROUND

1. Technical Field

The present disclosure relates to touch input technology and,particularly, to an apparatus and a method that can erase contentdisplayed on a touch screen.

2. Description of the Related Art

Many electronic devices employ touch screens to display content input byan input apparatus. On screen content can be erased by an erasingprogram, which may involve erasing all visible content or just somecontent depending on user input. However, operations required of a userto selectively erase content can be troublesome and time consuming.Therefore, there is room for improvement within the art.

BRIEF DESCRIPTION OF THE DRAWING

The components in the drawings are not necessarily drawn to scale, theemphasis instead being placed upon clearly illustrating the principlesof the disclosure. Moreover, in the drawing, like reference numeralsdesignate corresponding parts throughout the several views.

FIG. 1 is a block diagram of an apparatus capable of erasing contentdisplayed on a touch screen, according to an exemplary embodiment.

FIG. 2 is a schematic diagram showing a state of use of erasing contentdisplayed on the touch screen of the apparatus of FIG. 1, in accordancewith an exemplary embodiment.

FIG. 3 is a flowchart of a method capable of erasing content displayedon a touch screen in accordance with an exemplary embodiment.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, an apparatus 10 capable of erasing contentdisplayed on a touch screen is provided. The apparatus 10 includes atouch display unit 11, a control unit 12, a storage unit 13, an areadetecting unit 14, a time calculating unit 15, and an erasing unit 16.

The touch display unit 11 can determine touch coordinates of a touchoperation performed by a user with an input apparatus 20, such as a palmor a stylus, on the touch display unit 11. In detail, during the touchoperation, the touch display unit 11 determines a plurality of touchcoordinates of a first touched place of the touch operation on the touchdisplay unit 11, and determines a touch area of the first touched placeaccordingly. The touch display unit 11 further determines a touch traceof the touch operation on the touch display unit 11 according to thechanging of touch coordinates of touch places of the touch operation onthe touch display unit 11. In the embodiment, the touch display unit 11includes a touch screen and a touch controller.

The storage unit 13 is configured for storing size of a predeterminedarea and period of a predetermined time. In the embodiment, the size ofthe predetermined area and the period of the predetermined time arepreset by a user.

The area detecting unit 14 is configured for determining whether a sizeof the touch area of the first touched place is larger than thepredetermined area size. Meanwhile, the control unit 12 activates thetime calculating unit 15 to begin timing duration of the touch. When thesize of the touch area of the first touched place is larger than thepredetermined area size, the time calculating unit 15 continues tocalculate elapsed time of the touch operation on the touch display unit11, and deactivates the time calculating unit 15 when the elapsed timecalculated by the time calculating unit 15 is equal to the predeterminedtime or if the touch ceases before becoming equal to the predeterminedtime the timer 15 is restarted to time between consecutive touches. Thecontrol unit 12 further determines whether the touch trace of the touchoperation on the touch display unit 11 during timing matches otherpredetermined trace patterns. In the embodiment, the other predeterminedtrace patterns are: the touch operation is a back and forth slidingtouch operation and the size of a touch area of the touch operation onthe touch display unit 11 is greater than the predetermined area size.In the embodiment, the predetermined trace patterns of duration oftouch, area of touch, and characteristic movement of the touch arepreset by a user and changeable.

When the touch trace matches the predetermined trace patterns, thecontrol unit 12 generates an erasing signal. The erasing unit 16 erasesthe content displayed within the touched area of the touch display unit11 in response to the erasing signal.

When the touch trace does not match the predetermined trace pattern, thecontrol unit 12 restarts the time calculating unit 15 to calculate anelapsed time from the end of the touch operation to the start of a nexttouch operation of the input apparatus 20 on the touch display unit 11,and determines the touch operations of the input apparatus 20 is toinput content or commands other than the command to erase content, ifthe elapsed time is more than a predetermined time interval. In theembodiment, the predetermined time interval is equal to the predeterminetime period stored in the storage unit 13. The control unit 12 executesthe input commands or controls the touch display unit 11 to display theinput content.

Referring to FIG. 3, a method capable of erasing content displayed on atouch screen is provided.

In step S30, the touch display unit 11 determines a plurality of touchcoordinates of a first touched place of the touch operation on the touchdisplay unit 11, and determines the touch area of the first touchedplace accordingly.

In step S31, the area detecting unit 14 determines whether a size of thetouch area of the first touched place is larger than the predeterminedarea size. If yes, the procedure goes to step S32, otherwise, theprocedure goes to step S35.

In step S32, the control unit 12 activates the time calculating unit 15to calculate elapsed time of the touch operation on the touch displayunit 11, and determines whether the elapsed time calculated by the timecalculating unit 15 is equal to the predetermined time. If yes, theprocedure goes to step S33, otherwise, the procedure returns back tostep S32.

In step S33, the control unit 12 determines whether the touch trace ofthe touch operation on the touch display unit 11 during timing matchesthe predetermined trace pattern. If yes, the procedure goes to step S34,otherwise, the procedure goes to step S35.

In the embodiment, the predetermined trace pattern is: the touchoperation is a move back and forth operation and the size of a toucharea of the touch operation on the touch display unit 11 is alwayslarger than the predetermined area size. In the embodiment, thepredetermined trace pattern is preset by a user and changeable.

In step S34, the control unit 12 deactivates the time calculating unit15 when the time elapse time calculated by the time calculating unit 15is equal to the predetermined time, and generates the erasing signal.The erasing unit 16 erases the content displayed on the touch area ofthe touch display unit 11 in response to the erasing signal.

In step S35, the control unit 12 determines the touch operations of theinput apparatus 20 is to input contents or commands excepting thecommand to erase content when the elapsed time is larger than apredetermined time interval, and executes the input commands or controlsthe touch display unit 11 to display the input contents.

It is understood that the present disclosure may be embodied in otherforms without departing from the spirit thereof. Thus, the presentexamples and embodiments are to be considered in all respects asillustrative and not restrictive, and the disclosure is not to belimited to the details given herein.

What is claimed is:
 1. An apparatus capable of erasing contentcomprising: a touch display unit configured for determining touchcoordinates of a first touched place of a touch operation applied by aninput apparatus on the touch display unit, determining a touched area ofthe first touched place, and further configured for determining a touchtrace according to changes of the touch coordinates; a time calculatingunit; a storage unit configured for storing a predetermined area sizeand a predetermined time period; an area detecting unit configured fordetermining whether a size of the touched area is larger than thepredetermined area size; a control unit configured for activating thetime calculating unit to calculate a time duration of the touchoperation if the size of the touched area is larger than thepredetermined area size, deactivating the time calculating unit tocalculate the time duration when the time duration is equal to thepredetermined time period, determining whether the touch trace matches apredetermined trace pattern during the time duration, and furtherconfigured for generating an erasing signal if the touch trace matchesthe predetermined trace pattern; and an erasing unit configured forerasing content covered by the touch trace on the touch display unit inresponse to the erasing signal.
 2. The apparatus capable of erasingcontent as claimed in claim 1, wherein the input apparatus is a palm ofa user.
 3. The apparatus capable of erasing content as claimed in claim1, wherein the predetermined trace pattern is a moving back and forthgesture and the size of the touched area of the touch operation on thetouch display unit is larger than the predetermined area size.
 4. Theapparatus capable of erasing content as claimed in claim 3, wherein ifthe touch trace does not match the predetermined trace pattern, thecontrol unit is further configured for activating the time calculatingtime to calculate an elapsed time between the touch operation and a nexttouch operation of the input apparatus on the touch display unit, anddetermining the next touch operation is not to erase the content if theelapsed time is larger than a predetermined time interval.
 5. Theapparatus capable of erasing content as claimed in claim 4, wherein thepredetermined time interval is equal to the predetermined time periodstored in the storage unit.
 6. A method capable of erasing contentdisplay on a touch screen comprising: determining touch coordinates of afirst touched place of a touch operation applied by an input apparatuson the touch screen, and determining a touched area of the first touchedplace; determining whether a size of the touched area is larger than apredetermined area size; calculating a touch time duration of the touchoperation if the size of the touched area is larger than thepredetermined area size, and determining whether the touch time durationis equal to a predetermined time period; determining whether the touchtrace matches a predetermined trace pattern during the touch timeduration when the touch time duration is equal to the predetermined timeperiod; and generating an erasing signal if the touch trace matches thepredetermined trace pattern and erasing content covered by the touchtrace on the touch screen in response to the erasing signal.
 7. Themethod as claimed in claim 6, further comprising: determining the touchoperation of the input apparatus is not to erase the content if thetouch trace does not match the predetermined trace pattern.
 8. Themethod as claimed in claim 6, wherein the predetermined trace pattern isa moving back and forth gesture and the size of a touched area of thetouch operation on the display screen is always larger than thepredetermined area size.
 9. The method as claimed in claim 6, whereinthe predetermined area size is preset by a user.